Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 12
pubmed:dateCreated
2008-6-5
pubmed:abstractText
Tail-anchored proteins form a distinct class of membrane proteins that are found in all intracellular membranes exposed to the cytosol. These proteins have a single membrane insertion sequence at their C-terminus and display a large N-terminal portion to the cytosol. Despite their importance for various cellular processes, the mechanisms by which these proteins are recognized at and inserted into their corresponding target membrane remained largely unclear. Here we address this issue and investigate the biogenesis of tail-anchored proteins residing in the mitochondrial outer membrane. To that goal we developed a highly specific assay to monitor the membrane insertion of the model tail-anchored protein Fis1. Using this assay, we show that in contrast to all other import pathways in yeast mitochondria, none of the import components at the outer membrane is involved in the insertion process of Fis1. Both the steady-state levels of Fis1 and its in vitro insertion into isolated mitochondria were unaffected when mitochondria mutated in known import factors were analyzed. Fis1 was inserted into lipid vesicles, and importantly, elevated ergosterol contents in these vesicles inhibited this insertion. Collectively, these results suggest that Fis1 is inserted into mitochondria in a novel pathway where the unique lipid composition of the mitochondrial outer membrane contributes to the selectivity of the process. Thus, this work demonstrates a novel role for lipids in the biogenesis of mitochondrial protein.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9533
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
121
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1990-8
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Integration of tail-anchored proteins into the mitochondrial outer membrane does not require any known import components.
pubmed:affiliation
Institut für Physiologische Chemie der Universität München, Munich, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't